GCN Circulars
GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
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To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.
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subject:"Swift"body:"GRB"submitter:"Judith Racusin"4055 results found.
- LIGO/VIRGO G184098: Summary of VLA results for iPTF15cyk
- LIGO/Virgo G184098: MASTER final result
- LIGO/Virgo G211117: Refined localization from CBC parameter estimation
- LIGO/Virgo G211117: Preliminary VLA observation summary of PS15dpn
- LIGO/Virgo G211117: Further Swift-XRT sources
- LIGO/Virgo G211117: INAF NOT follow-up of PanStarrs candidates
- LIGO/Virgo G184098: Refined localizations from CBC parameter estimation
- LIGO/Virgo G211117: Updated FAR estimate based on offline re-analysis
- LIGO/Virgo G184098: Updated FAR estimate
- LIGO/Virgo G211117: Distance estimate from GW data compared to redshift of PS15dpn
- LIGO/Virgo G211117: Swift observations of PS15dpn
- LIGO/Virgo G211117: iPTF Observations of PS15dpn
- LIGO/Virgo G211117: PESSTO classification of MASTER J165420.77-615258
- LIGO/Virgo G211117: VLA follow-up
- LIGO/Virgo G211117: Pi of the Sky observations
- LIGO/Virgo G211117: VISTA imaging
- LIGO/Virgo G211117: Subaru Hyper Suprime-Cam follow-up observation
- LIGO/Virgo G211117: MASTER OT in ESO138-006 galaxy
- LIGO/Virgo G211117: Further Swift-XRT sources
- LIGO/Virgo G211117: Liverpool Telescope classification of EM candidates
- LIGO/Virgo G211117: Summary of Pan-STARRS transients
- LIGO/Virgo G211117: INAF TNG follow-up of Kanata telescope candidate
- LIGO/Virgo G211117: Fermi/LAT observations
- LIGO/Virgo G211117: Liverpool Telescope classification of EM candidates
- LIGO/Virgo G211117: Gemini classification of 7 Pan-STARRS transients
- LIGO/Virgo G211117: LOFAR follow-up
- LIGO/Virgo G211117: Liverpool Telescope classification of EM candidates
- LIGO/Virgo G211117: PESSTO classification of Pan-STARRS transients
- LIGO/Virgo G211117: MASTER OTs 26.XII.2015 - 01.I.2016
- LIGO/Virgo G211117: CSS/CRTS observations on 29/30 Dec 2015 UT
- LIGO/Virgo G211117: La Silla - QUEST observations 2015 Dec 28 - 30
- LIGO/Virgo G211117: Liverpool Telescope classification of EM candidates
- LIGO/Virgo G211117: FLOYDS Classification of SMTJ13331687-1607330 as a Two-Week-Old Type Ia Supernova
- LIGO/Virgo G211117: LBT follow-up imaging of iPTF15fhq
- LIGO/Virgo G211117: 44 transients from Pan-STARRS data during 2015-12-28/30
- LIGO/Virgo G211117: MAXI/GSC observations
- LIGO/Virgo G211117: Liverpool Telescope followup of EM candidates
- LIGO/Virgo G211117: VLA follow-up
- LIGO/Virgo G211117: LBT Follow-up of iPTF15fen
- LIGO/Virgo G211117: MAGIC very-high energy gamma-ray observations
- LIGO/Virgo G211117: INAF TNG follow-up of MASTER OT J020906.21+013800.1
- LIGO/Virgo G211117: OAO-WFC NIR follow-up observations
- LIGO/Virgo G211117: SkyMapper observations and transient candidate
- LIGO/Virgo G211117: MASTER Observations of the 3 iPTF candidates
- LIGO/Virgo G211117: Optical Observations with Kiso Schmidt telescope and KWFC
- LIGO/Virgo G211117: List of near-term future observation regions by Project Mini-GWAC of SVOM
- LIGO/Virgo G211117: iPTF Optical Transient Candidates
- LIGO/Virgo G211117: La Silla - QUEST observations 2015 Dec 28, 29
- LIGO/Virgo G211117: Further Swift-XRT sources
- LIGO/Virgo G211117: DESGW program observations with DECam
- LIGO/Virgo G211117: Optical NIR observation with Kanata telescope
- LIGO/Virgo G211117: Fermi GBM Observations
- LIGO/Virgo G211117: Optical follow-up with Kanata telescope
- LIGO/Virgo G211117: MASTER Observations and Inspection + OT
- LIGO/Virgo G211117: INTEGRAL was inactive at the time of the event
- LIGO/Virgo G211117: Pan-STARRS1 observations 2015-12-28
- LIGO/Virgo G211117: INAF VST-ESO PARANAL observations
- LIGO/Virgo G211117: Further Swift-XRT sources
- LIGO/Virgo G211117: Swift-XRT sources
- LIGO/Virgo G211117: SWASP optical observations
- LIGO/Virgo G211117: MASTER possible OT detection at the begining of inspection
- LIGO/Virgo G211117: Identification of a GW CBC Candidate
- LIGO/Virgo G184098: Fermi-LAT search for high-energy gamma-ray counterpart
- LIGO/Virgo G184098: LOFAR follow-up
- LIGO/Virgo G184098: Results of of 2nd epoch of ASKAP follow-up
- LIGO/Virgo G194575: Updated significance from offline GW analysis
- LIGO/Virgo G194575: Fermi GBM Observations
- LIGO/Virgo G194575: VLA follow-up
- LIGO/Virgo G194575: Liverpool Telescope observations of iPTF-15dld and iPTF-15dni
- LIGO/Virgo G194575: La Silla QUEST, Pan-STARRS and PESSTO observations of iPTF15dld
- LIGO/Virgo G194575: Swift observations if iPTF15dld
- GRB 151027A: Hankasalmi optical observations
- LIGO/Virgo G194575: INAF-TNG/Asiago Telescope follow-up of iPTF15dld
- LIGO/Virgo G194575: INAF-Asiago Telescope further analysis of iPTF candidates
- LIGO/Virgo G194575: INAF-Asiago Telescope follow-up of iPTF candidates
- LIGO/Virgo G194575: VLA follow-up
- LIGO/Virgo G194575: MAXI/GSC further analysis
- LIGO/Virgo G194575: LT Spectroscopy of iPTF-15dmk
- LIGO/Virgo G194575: LT Spectroscopy of iPTF candidates
- LIGO/Virgo G194575: INAF-TNG follow-up of iPTF15dkm and iPTF15dlj
- LIGO/Virgo G194575: VLA follow-up
- LIGO/Virgo G194575 : RATIR Observation of La Silla - QUEST Candidate
- LIGO/Virgo O1 extended until January 12
- LIGO/Virgo G194575: iPTF Optical Transient Candidates
- LIGO/Virgo G194575: MASTER Optical Inspection
- LIGO/Virgo G194575: Swift observations of LSQ15bjb
- LIGO/Virgo G194575: INAF-TNG spectra of LSQ15bjb
- LIGO/Virgo G194575: GROND multi-color observations
- LIGO/Virgo G194575: further Pan-STARRS observations of the RA=1hr localisation region
- LIGO/Virgo G194575: ASKAP followup
- LIGO/Virgo G194575: INAF-TNG follow-up of LSQ15bjb
- LIGO/Virgo G184098: VLA follow-up of iPTF15cyk
- LIGO/Virgo G194575 : La Silla - QUEST followup
- LIGO/Virgo G194575: Near-infrared follow-up with OAO-WFC
- LIGO/Virgo G194575: Kanata/J-GEM optical follow-up
- LIGO/Virgo G194575: Pi of the Sky observations
- LIGO/Virgo G194575: MAXI/GSC observations
- LIGO/Virgo G194575: Swift observations
- LIGO/Virgo G194575: CQUEAN/LOAO observations
- Possible Fermi-LAT Gamma-ray counterpart for LIGO/Virgo G194575